Polymorphism of mitochondrial DNA and distribution of cytoplasmic symbionts in the populations of two-spot ladybird beetle Adalia bipunctata

Abstract

In geographically distant populations of ladybird beetle Adalia bipunctata from Eurasia mitotypes and infection with symbiotic bacteria Spiroplasma and Rickettsia were determined. All populations examined demonstrated mtDNA polymorphism and striking differences in prevalence of bacteria (from about 50% of individuals infected with Spiroplasma in St. Petersburg population and 50% of the Rickettsia prevalence in Kem' population to complete absence of bacteria in the population from Archangelsk). In the populations studied a total of 14 mitotypes were discovered, including two mitotypes that were remarkably different from the others in nucleotide composition. Mitotype 10, which was the most different from all the others, was found in all populations from Germany to Transbaikalia, excluding the population from Tashkent. Linkage disequilibrium between mitotype 10 and the Rickettsia infection was confirmed. Infection with the Spiro plasma bacteria was typical of the individuals with haplotype 1 and relative to it. The results obtained sup ported the conclusion on the association between infection with Spiroplasma and Rickettsia and certain mito type of A. bipunctata, which was the consequence of either absence or rare horizontal transfer of symbionts and ancientness of the first contact between the bacteria and A. bipunctata ladybird beetles.

Comparative study of mtDNA in species of the genus Adalia (Coleoptera: Cocinellidae) and origin of ancient mitochondrial haplotypes in the gene pool of Adalia bipunctata

“…In order to understand the factors determining the preservation of the mitochondrial haplotypes H9 and H10 in the A. bipunctata gene pool, it is important to take into consideration that only individuals carrying mitochondrial haplotypes H9 and H10 are mostly infected with the cytoplasmic symbiotic bacterium Rickettsia AB (Schulenburg et al, 2002;Jiggins & Tinsley, 2005;Shaikevich et al, 2012), which kills ladybird males at an early stage in their embryonic development. We found no individuals of A. bipunctata carrying the other mitochondrial haplotypes infected with Rickettsia, however other studies report cases of infection of individuals with the mitochondrial haplotype H7 (Schulenburg et al, 2002;Jiggins & Tinsley, 2005).…”

Variation in male and female mating behaviour among different populations of the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)

“…Both Rickettsia and Spiroplasma infections have been identified in UK populations (Weinert et al, 2007), although the Cambridge population has only been found to be infected with the Rickettsia bacteria, at a prevalence of around 7% (Hurst et al, 1993). Russian populations also harbour both Rickettsia and Spiroplasma infections, with prevalence estimates ranging from 5-50% and 18-44%, respectively (Schulenburg et al, 2002;Shaikevich et al, 2012). However, some Russian populations have also been identified as being infected with the bacteria Wolbachia, with prevalence estimates of around 23% (Schulenburg et al, 2002).…”